Topical tretinoin is used in the treatment of acne and other dermatoses. The most common side-effects are itching, dryness and reddening of the skin. We report an additional cutaneous reaction, which occurred in patients using topical tretinoin. Pyogenic granulomas developed in two patients with acne and in one with dermatofibroma following application of tretinoin. The granulomas grew on the lesions after 2-3 weeks of therapy initiation. All patients were men and the granulomas developed in their trunk. The lesions resolved when topical tretinoin was ceased. Although the number of patients reported is too small to estimate the true incidence of this reaction, it is likely that dermatologists will encounter similar reactions in patients treated with topical tretinoin for acne or other reasons.